Abstrakt
Observations of intense upgoing electron beams and diffuse ion beams have been reported during a pass by Cassini in a downward current auroral region, nearby a source region of Saturn kilometric radiation. Using the Cassini Radio and Plasma Wave Science (RPWS) instrument low frequency waveform receiver and the Cassini Plasma Spectrometer Investigation (CAPS) instrument we have been able to identify ion cyclotron harmonic waves associated with the particle beams.
These observations indicate similarities with terrestrial auroral emissions, and may be a source of wave-particle interactions. We fit the observed plasma electron distribution with drifting Maxwellians and perform a linear numerical analysis of plasma wave growth.
The results are relevant to ion heating and possibly to electron acceleration.